Calculating the Distance Between Two Points On A Line:

The equation for calculating the distance between two points on a line is the square root of y2 - y1 squared plus x2 - x1 squared:

Sample Problem #1:
Finding the distance beween Line AB
Point A = (1,3)
Point B = (8,0)

Equation:
d(A,B) = sqrt [ (x2 - x1) 2 + (y2 - y1) 2 ]
First of all, put in all the number of to you equation -
the square root of (8-1 ^2) + (0-3 ^2)
Then, do the math in the brackets -
the square root of (49) + (9)
Add both brackets together -
the square root of 58
Then find the square root of that number -
= 7.61577
Round that number to the tenth decimal place -
= 7.6
The answer will always be a positive because we are finding a distance and a distance cannot be negative.

Sample Problem #2:
Finding the distance between Line CD
Point C= (0,0)
Point D= (6,8)
Equation:
d(C,D) = sqrt [ (x2 - x1) 2 + (y2 - y1) 2 ]
d=sqrt [ (6-0)2 + (8-0)2 ]
d=sqrt [ (36) + (64) ]
d=squrt [100]
d=10

Sample Problem #3:
Finding the distance between the line shown:
external image f-110-1.gif

First Point: (-5,8)
Second Point: (0,-4)
Equation:
d = sqrt [ (x2 - x1) 2 + (y2 - y1) 2 ]
d= sqrt [ (0- -5) 2 + (-4 - 8) 2 ]
d= sqrt [ (25) + (144) ]
d= sqrt [ (169) ]
d= 13

To try this on your own do some of these examples:

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